docs: def _actor_property(self, event, cameo_code, actor_regex):
          """
          Determine the property to use for modeling an actor
          Args:
              event: one of "event1", "event2" or "event3"
              cameo_code: one of the cameo codes
              actor_regex: one of the regexes above
  
          Returns:
  
          """
          if cameo_code not in self.mapping:
              return None
  
          arguments = self.mapping[cameo_code][event + "-arguments"]
          if not isinstance(arguments, list):
              arguments = [arguments]
  
          result = list()
          for a in arguments:
              match = re.search(actor_regex, a)
              if match:
                  result.append(match.group(1))
          return result[0] if len(result) > 0 else None